In the time of the Qing Dynasty, the Emperor Yongzheng created a secret army known as the Guillotines. It was the job of the Guillotines to protect the Emperor by killing anyone who posed a threat to him or his rule. After 348 successful missions to eliminate their target, the 349th assignment proves to be their last.

In a city of love and prosperity, a city of lost hope and premature death, veteran detective Hei feels it all: the hurt, the helplessness, the horror. When his father-in-law, the billionaire benefactor Kim, is gruesomely murdered in his palatial mansion, he enlists the assistance of his former partner turned private detective.